Method for correcting measurement vibration of deformation video of multi-constrained wind tunnel test model

Abstract

The invention discloses a method for correcting the measurement vibration of a deformation video of a multi-constrained wind tunnel test model. The method comprises the following steps: arranging a video observation camera; establishing an image point projection observation equation; establishing rigid body and extreme line constraint equations; constructing an iterative equation; iteratively solving an optimal solution of an equation set; and reconstructing a current camera posture and a model posture. The method has the positive effects that rigid body constraint conditions of body feature points of the test model and rigid body constraint conditions of wallboard feature points of a wind tunnel test section are simultaneously utilized, collinear constraint conditions of wing feature points of the test model in multi-view measurement geometry are further increased, and all the constraint conditions are creatively changed into uniform iterative equations; the method has the advantages that the iterative convergence is rapid, the solving accuracy is high, the position and posture of the test model cane be simultaneously solved, and the like.

Description

technical field [0001] The invention relates to the fields of computer vision and photogrammetry, in particular to a multi-constraint wind tunnel test model deformation video measurement vibration correction method, which is an engineering application of machine vision measurement technology in high-speed wind tunnel tests. Background technique [0002] During the wind tunnel test, the test model wing is elastically deformed by the aerodynamic load. For a wing with a large aspect ratio, this deformation will seriously affect the aerodynamic characteristics of the aircraft. If it deviates from the design requirements, the test data must be corrected. Therefore, it is necessary to accurately measure the deformation of the test model during the wind tunnel test. volume size. However, the non-contact optical measurement method has little interference to the wind tunnel flow field, high measurement accuracy, and does not change the geometric shape of the test model. It is curren...

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Problems solved by technology

However, only using the rigid body constraints of the model fuselage can only correct the relative position and attitude between the two cameras, and cannot correct the overall offset of the camera coordinate system in the world coordinate system of the test section, so the current attitude and attitude of the test model cannot be obtained. Location

At the same time, since the fuselage of the test model only occupies a small part of the effective measurement area, this method does not make full use of all the measurement features, and this method is very sensitive to the internal parameters of the camera, and any slight deviation of the internal parameters of the camera will lead to correction The result makes a big difference

The literature "Camera Position Coordinates and Attitude Angle Determination for Model Deformation Video Measurement" (Luo Chuan, Zhang Zhengyu, Sun Yan, etc. Experimental Fluid Mechanics. 2010, (6): 88-91) describes the use of the angle cone method to correct the relative angle of a single camera. Based on the offset of the world coordinate system in the wind tunnel test section, this method uses the image coordinates of the characteristic mark points on the wall plate of the test section to correct the vibration deviation of each camera independently, but this method does not effectively use the relationship between each camera and the test model. Therefore, after correcting the vibration deviation of the camera pose, an additional step is required to reconstruct the position and pose of the test model

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